A method has been developed for accurate determination of 5-Hydroxyindoleacetic acid and 5-Hydroxytyyptamine. Because of the considerable time involved in developing and perfecting this method there is no clinical data as yet. The methodology is currently the subject of a paper which will be submitted or publication shortly. Sixty-two cerebral spinal fluids have been analyzed for beta-2-microglobulins. Although the data is not as yet completed it appears that beta-2-microglobulin is elevated in the cerebropsinal fluids of patients with both leukemia and lymphoma who have documented central nervous system disease by other criteria, such as presence of blasts on cytocentrifuge and protein elevations. Because most of the lumbar punctures were obtained because of clinical suspicion of central nervous system disease, the elevation of the beta-2-microglobulin tended to be confirmatory rather than predictive. Beta-2-microglobulins also appeared to decrease with remission induction and do not appear to be affected by intrathecal chemotherapy. Therefore, although it appears that beta-2-microglobulins are increased in patients with CNS involvement, clinical criteria are probably better predictors of disease.